For example, JP-2006-302759-A discloses a battery pack used in a power tool. In the battery pack, a battery case is L-shaped in a side view, and an electrode terminal to be connected to an electrode terminal of a power tool body is disposed at an upper end of the battery case.
In the battery pack, when the battery pack detached from the power tool is placed in a sideways failing-down state, in case that the shock is applied to the battery pack, if a portion that has received its shock is in the vicinity of the electrode terminal, the shock is readily given onto the electrode terminal, with the result that the electrode terminal can be damaged or broken.